killerrudy
New member
Well I have failed 3 times now. Each time for the HC at idle. Max is 140. First trip I blew 360. Replaced the spark plugs. Then it went down to 160. The only thing that I changed from last year was the 255 fuel pump. So I thought maybe it was over running the stock fpr at idle. Picked up an adjustable and set it to 43. Failed HC 171. The guy let me run again and I turned the fp down to 20 and it still blew 170? I am dazed and confused. I passed last year no problems. Now I replace the fuel pump and my truck is pissed off? Suggestions? How else to lower unburnt fuel at idle? I pass everything else with flying colors. :rant: